Sertoli cells metabolize progesterone to testosterone (T) and 5a-dihydrotestosterone (DHT)

[miquelangeles]

ABSTRACT.
The ability of Sertoli cells to metabolize progesterone to testosterone (T) and 5a-dihydrotestosterone (DHT) was investigated in vitro. Cultures of Sertoli cells isolated from testes of 80-day-old rats were incubated with [7(n)-3 H]progesterone (10/iCi/3.0 nmol) for 0.5, 1, 2, and 3 h. The amount of progesterone converted to T, androstenedione (A), DHT, 17a-hydroxyprogesterone, and 20a-dihydroprogesterone was calculated on the basis of crystallization data. The amount of substrate converted to the various steroids increased between 0.5-3 h of incubation. During this period, T increased 6-fold; A, 2-fold; DHT, 4-fold; 17a-hydroxyprogesterone, 3-fold; and 20a-dihydroprogesterone, 12- fold. The amount of substrate converted to C-19 steroids (T, A, and DHT) increased linearly with time; 19.4 ng androgen/1 x 106 cells were formed within 3 h, the largest amount (11.83 ng) being DHT. Although the amount of 3H-labeled C-19 steroids formed from [3 H]- progesterone by Sertoli cells is relatively small (1.8% conversion) compared to T formation by whole testicular tissue or by isolated interstitial cells, the ability of Sertoli cells to form T and DHT from progesterone may be physiologically important in the local regulation of Sertoli cell function and spermatogenesis. (Endocrinology 103: 1335, 1978)

Progesterone Metabolism by Cultured Sertoli Cells*

The ability of Sertoli cells to metabolize progesterone to testosterone (T) and 5α-dihydrotestosterone (DHT) was investigated in vitro. Cultures of Sertoli cell

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[Mauritio]

Interesting!
Thanks for sharing.

So topical progesterone on the testicles it is then ...
Have you tried it before?

20aDHP seems to be biologically inactive.

 

[miquelangeles]

I tried tiny amounts a while ago but I'll look into it again. I think there are a few studies showing that it can shrink the prostate.

Also these:

Comparative Ability of Seminiferous Tubules and Interstitial Tissue of Rat Testes To Synthesize Androgens from Progesterone-4-14C in Vitro

Tubules and interstitial tissue from 1½ testes were isolated and incubated separately with progesterone-4-14C, and the resulting androgens were analyzed. Both the interstitial tissue and the seminiferous tubules were capable of transforming progesterone to 17-hydroxyprogesterone, Δ4-androstene-3,17-dione and testosterone, although the interstitial tissue was considerably more active than the tubules. These results confirm previous evidence that the interstitial tissue is the principal source of testicular androgens, but show that the seminiferous tubules are also capable of significant androgen biosynthesis in vitro. (Endocrinology76: 646, 1965)

Conversion of Cholesterol to Androgens by Rat Testes: Comparison of Interstitial Cells and Seminiferous Tubules

Interstitial cells were separated from the tubules of testes of young and mature rats. When interstitial cells were incubated with cholesterol-7α-3H this substrate was converted to testosterone-3H and androstenedione-3H. Under similar conditions tubules from the same testes failed to convert cholesterol to either androgen. To the extent that cholesterol is the physiological precursor of steroid hormones, these results confirm previous evidence that interstitial cells represent the major and probably the only source of testicular androgens. In confirmation of a previous report, both interstitial cells and tubules were found to convert progesterone-4-14C to testosterone-14C and to androstenedione- 14C, although the physiological significance of this observation remains uncertain. (Endocrinology84: 488, 1969)

 

[Nokoni]

Very interesting, thanks. At a dose of 2 drops each day (Progestene) for 2 or 3 days on the scrotum I noticed a masculinizing effect – more assertive, eagerness to schlep the shopping, etc. Pretty surprising, though the magnitude of the effect may be related to my age (70 yo male). I think I'll keep experimenting with it for a while. I've attached the study for anyone that's interested.